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Hiotographic 

Sciences 

Corporation 


23  WEST  MAIN  STREET 

WEBSTER,  NY.  14580 

(716)  873-4503 


CIHM/ICMH 

Microfiche 

Series. 


CIHM/iCIVIH 
Collection  de 
microfiches. 


V 


Canadian  Institute  for  Historical  Microreproductions 


Institut  Canadian  de  microreproductions  historiques 


1980 


Technical  and  Bibliographic  Notes/Notes  techniques  et  bibliographiques 


The  Institute  has  attempted  to  obtain  the  best 
original  copy  available  {"or  filming.  Features  of  this 
copy  which  may  be  bibliographicaliy  unique, 
which  may  alter  any  of  the  images  in  the 
reproduction,  or  which  may  significantly  change 
the  usual  method  of  filming,  are  checked  below. 


0    Coloured  covers/ 
Couverture  de  couleur 


D 
D 

n 


n 


D 


Covers  damaged/ 
Couverture  endommagde 

Covers  restored  and/or  laminated/ 
Couverture  restaur6e  et/ou  pelliculde 

Cover  title  missing/ 

Le  titre  de  couverture  manque 


□    Coloured  maps/ 
Cartes  gdographiques  en  couleur 

□    Coloured  ink  (i.e.  other  than  blue  or  black)/ 
Encre  de  couleur  (i.e.  autre  que  bleue  ou  noire) 


D 


Coloi-red  plates  and/or  illustrations/ 
Planches  et/ou  illustrations  en  couleur 

Bound  with  other  material/ 
Reli6  avec  d'autres  documents 

Tight  binding  may  cause  shadows  or  distortion 
along  interior  margin/ 

La  reiiure  serr6e  peut  causer  de  I'ombre  ou  de  la 
distortion  le  long  de  la  marge  intdrieure 

Blank  leaves  added  during  restoration  may 
appear  within  the  text.  Whenever  possible,  these 
have  been  omitted  from  filming/ 
II  se  peut  que  certaines  pages  blanches  ajoutdes 
lors  d'une  restauration  apparaissent  dans  le  texte, 
mais,  lorsque  ceia  6tait  possible,  ces  pages  n'ont 
pas  6t6  filmdes. 


Additional  comments:/ 
Commentaires  suppl6mentaires: 


L'Institut  a  microfilm^  le  meilleur  exemplaire 
qu'il  lui  a  6t6  possible  de  se  procurer.  Les  ddtaiis 
de  cet  exemplaire  qui  sont  peut-Atre  uniques  du 
point  de  vue  bibliographique,  qui  peuvent  modifier 
une  image  reproduite,  ou  qui  peuvent  exiger  une 
modification  dans  la  mdthode  normale  de  filmage 
sont  indiqu6s  ci-dessous. 


I      I    Coloured  pages/ 


D 


Pages  de  couleur 

Pages  damaged/ 
Pages  endommagdes 

Pages  restored  and/oi 

Pages  restaurdes  et/ou  pellicul6es 

Pages  discoloured,  stained  or  foxei 
Pages  d6color6es,  tachetdes  ou  piqu6es 

Pages  detached/ 
Pages  ddtachdes 


I — I  Pages  damaged/ 

I      I  Pages  restored  and/or  laminated/ 

I — I  Pages  discoloured,  stained  or  foxed/ 

I      I  Pages  detached/ 


I      I    Showthrough/ 


Transparence 


□    Quality  of  print  varies/ 
Qualitd  indgale  de  I'impression 

I      I    Includes  supplementary  material/ 


Comprend  du  materiel  supplementaire 

Only  edition  available/ 
Seule  Edition  disponible 


Pages  wholly  or  partially  obscured  by  errata 
slips,  tissues,  etc.,  have  been  refilmed  to 
ensure  the  best  possible  image/ 
Les  pages  totalement  ou  partiellement 
obscurcies  par  un  feuillet  d'errata,  une  pelure, 
etc.,  ont  6t6  fiimdes  d  nouveau  de  fafon  d 
obtenir  la  meilleure  image  possible. 


0This  item  is  filmed  at  the  reduction  ratio  checked  below/ 
Ce  document  est  filmi  au  taux  de  reduction  indiqu6  ci-dessous. 


10X 


14X 


18X 


22X 


26X 


30X 


12X 


16X 


20X 


24X 


28X 


32X 


s 

I 
fier 

e 
ge 


The  copy  filmed  here  has  been  reproduced  thanks 
to  the  generosity  of: 

National  Library  of  Canada 


The  images  appearing  here  are  the  best  quality 
possible  considering  the  condition  and  legibility 
of  the  original  copy  and  in  keeping  with  the 
filming  contract  specifications. 


L'exemplaire  film6  fut  reproduit  grdce  d  la 
g6n6rosit6  de: 

Bibliothdque  nationale  du  Canada 


Les  images  siiivantes  ont  6t6  reproduites  avec  le 
plus  grand  soin,  compte  tenu  de  la  condition  at 
de  la  nettet6  de  l'exemplaire  filmi,  et  en 
conformity  avec  les  conditions  du  contrat  de 
filmaga. 


Original  copies  in  printed  paper  covers  are  filmed 
beginning  with  the  front  cover  and  ending  on 
the  last  page  with  a  printed  or  illustrated  impres- 
sion, or  the  back  cover  when  appropriate.  All 
other  original  copies  are  filmed  beginning  on  the 
first  page  with  a  printed  or  illustrated  impres- 
sion, and  ending  on  the  last  page  with  a  printed 
or  Illustrated  impression. 


Les  exemplaires  originaux  dont  la  couverture  en 
papier  est  imprim^e  sont  film6s  en  commenpant 
par  le  premier  plat  et  en  terminant  soit  par  la 
dernidre  page  qui  comporte  une  empreinte 
d'impression  ou  d'illustration,  soit  par  le  second 
plat,  selon  le  cas.  Tous  les  autres  exemplaires 
originaux  sont  film6s  en  commenpant  par  la 
premidre  page  qui  comporte  une  empreinte 
d'impression  ou  d'illustration  et  en  terminant  par 
la  dernidre  page  qui  comporte  une  telle 
empreinte. 


The  last  recorded  frame  on  each  microfiche 
shall  contain  the  symbol  — ^-  (meaning  "CON- 
TINUED "),  or  the  symbol  V  (meaning  "END"), 
whichever  applies. 


Un  des  symboles  suivants  apparaitra  sur  la 
dernidre  image  de  cheque  microfiche,  selon  le 
cas:  le  symbole  -^signifie  "A  SUIVRE",  le 
symbole  V  signifie  "FIN". 


Maps,  plates,  charts,  etc.,  may  be  filmed  at 
different  reduction  ratios.  Those  too  large  to  be 
entirely  included  in  one  exposure  are  filmed 
beginning  in  the  upper  left  hand  corner,  left  to 
right  and  top  to  bottom,  as  many  frames  as 
required.  The  following  diagrams  illustrate  the 
method: 


Les  cartes,  planches,  tableaux,  etc.,  peu>'er?t  dtre 
film6s  d  des  taux  de  reduction  diff6r6r...s. 
Lorsque  le  document  est  trop  grand  pour  dtre 
reproduit  er  un  seul  clich6,  il  est  film6  d  partir 
de  Tangle  supdrieur  gauche,  de  gauche  d  droite, 
et  de  haut  en  bas,  en  prenant  le  nombre 
d'images  ndcessaire.  Les  diagrammes  suivants 
illustrent  la  mdthode. 


ita 


lure, 


: 


2X 


1 

2 

3 

1 

2 

3 

4 

5 

6 

Vol.  I. 


J^o.  VI. 


BULLETIN 


OF    THE 


C 


A 


HICAGO /ACAD.-MY  OF  OCIENCES. 


S- 


BOULDER   CLAYS. 

ON  THE  MICROSCOPIC  STRUCTURE  OF  CERTAIN 

BOULDER  CLAYS  AND  THE  ORGANISMS 

CONTAINED  IN  THEM. 


DR.  GEORGE  M.  DAWSON,  D.  S.,  F.  G.  S.,  &c., 

Assisfan/  Director  of  ihe   Geological  Stiruey  of  Canadn. 


•    CHICAGO: 

JOHN    MORRIS   COMPANY,    PRINTERS. 
1885. 


Vol.  I.  J^o.  VI. 


BULLETIN 


OF    THE 


C-HiCAGO  Academy  of  Sciences. 


BOULDER  CLAYS. 

ON  THE  MICROSCOPIC  STRUCTURE  OF  CERTAIN 

BOULDER  CLAYS  AND  THE  ORGANISMS 

CONTAINED  IN  THEM, 


DR.  GEORGE  M.  DAWSON,  D.  S.,  F.  G.  S.,  &c., 

Asnslant  Director  of  the  Geological  Sui-vey  of  Canada. 


CHICAGO : 

IRINTEIJ    FOR   THE   ACADEMY. 
1885. 


BULLETIN 

OF  tub: 

Chicago  Academy  of  Sciences. 


BOULDER-CLAYS. 

ON  THE  MICROSCOPIC  STRUCTURE  OF  CERTAIN  BOULDER- 
CLAYS  AND  THE  ORGANISMS  CONTAINED  IN  THEM. 

BY  DR.  GEORGE  M.  DAWSON,  D.  S.,  F.  G.  S.,  F.  R.  S.  eAN.,  ASSOCIATE 

R.   S.   M.,    AND    ASSISTANT     DIRECTOR    OF    THE 

GEOLOGICAL   SURVEY   OF    CANADA. 

(HEAD   BEPOUK   THE   CHICAGO   ACADEMK    OF  SCIENCES  JINE   9,  1885.  IIY    II.  A.  .lOHNSON,  M.  I).,  V.  H.  M.  S.) 

In  a  paper  read  before  the  Academy  in  January,  1884,  and  printed  in 
the  bulletins  of  the  Academy  (vol.  i,  No.  4),  H.  A.  Johnson,  M.  D.,  and 
B.  W.  Thomas,  F.  R.  M.  S.,  gave  the  results  of  an  investigation  by  them 
of  microscopic  organisms  \n  the  boulder  clay  of  Chicago  and  vicinity.  This 
paper  refers  principally  to  certain  remarkable  bodies  first  found  by  these 
gentlemen  in  1865-66-67,  in  specimens  of  the  clay  through  which  the  lake 
tunnel,  which  supplies  the  city  of  Chicago  with  water  from  Lake  Mich- 
igan, was  being  constructed.     On  the  completion  of  the  tunnel  large  num- 
bers of  the  same  bodies  were  observed  in  the  filtrate  from  the  city  water  sup- 
ply, and  which   were  subsequently  proved  to  be  identical  with  organisms 
described  in  1871  by  Sir  J.  VV.  Dawson  from  the  Devonian  shales  of  Kettle 
Point,  Lake  Huron,     They  have  since  been  observed  in  the  Devonian  rocks 
of  a  number  of  widely  separated  localities,  and  are  now  K-lieved  by  Sir  J. 
W.  Dawson  to  be  macrospores    of  rhizocarps.*     In  accord<3nce  with    this 
view  the  generic  name  of  Protosalvinia  is  proposed  by  Dawson  in  the  paper 
above  referred   to  instead  of  Spomngites,  which  term  is,  however,  still  used 
in  this  paper.     Properly  speaking,  this  term  would  apply  to  the  Sporangia 
conf.  -ning   these   macrospores,    and    which  are  absent    in    the  specimens 
ui    question.       Mr.   Thomas,    in     a    note    to   the    paper    first    quoted, 
refers    to   the    additional    discovery     in    boulder-clay     from     Minnesota, 
sent  to   him  by  Prof.  N.  H.  Winchell,  of  several  species  of  Foraminifera, 
evidently    derived     from    the    Cretaceous    rocks    of    that    region.    Since 

lu     T*?*"^.","^-,  ^-  ^-  ^•.'  '^^^.'  ^"''  ^''"-  "  ^"°"'  °f  Science."  vol.  i.     See  also  paperl^y 
Mr.  J.  M.  Clarke,  American  Journal  of  Science,  vol.   xxix,  p.  284. 


6o 

this  announcement  Mr.  Thomas  has  mounted  for  the  microscope  and 
examined  many  samples  of  boulder-clays  from  various  places,  and  has  favored 
me  from  time  to  time  with  a  number  of  his  preparations.  He  has  also  kindly 
prepared  and  mounted  specimens  of  several  boulder-clays  and  allied  mate- 
rials collected  in  Manitoba  and  the  Saskatchewan  region.  At  his  request 
the  notes  made  by  me  on  these  last  and  on  a  few  of  those  first  mentioned 
are  here  offered.  Tiiis  paper  must,  however,  be  understood  to  be  merely  of 
a  preliminary  and  general  character,  being  based  on  the  examination  of  less 
than  one  hundred  microscopic  preparations.  It  .ay,  it  is  hoped,  be  supple- 
mented later  by  a  more  detailed  report,  including  the  discussion  of  a  larger 
suite  of  specimens,  from  a  greater  number  of  localities. 

The  microscopical  investigation  of  these  boulder  clays  has  resulted  in  the 
discovery  of  many  objects  which,  while  evidently  of  organic  origin,  ar^  very 
difficult  to  name  or  classify,  and  require  comparison  with  a  wide  range  of 
bodies  and  reference  to  many  works  for  that  purpose.  Mr.  Thomas  has  also 
found  that  even  in  the  case  of  those  clays  with  which  he  is  most  familiar, 
each  new  lot  of  preparations  mounted  is  almost  sure  to  show  forms  not  be- 
fore observed,  and  that  the  field  is  an  ever-widening  one. 

It  is  now, therefore, proposed  merely  to  denote  the  classes  of  objects  so  far 
observed  in  the  various  boulder-clays,  and  when  possible  the  genera  to 
which  the  organisms  belong,  without  attempting  to  catalogue  them  specifi- 
cally. Neither  is  it  here  intended  to  enter  into  any  further  discission  as  to 
the  nature  of  the  Macrospores  occurring  in  some  of  the  clays. 

It  should  also  be  stated  that  most  of  the  objects  on  the  many  slips 
examined,  have  been  indicated  by  maltwood  markings  by  Mr.  Thomas,  a 
circumstance  greatly  reducing  the  amount  of  labor  involved  in  going  over 
the  material.* 

BOULDER-CLAVS  OK   CHICAGO   AND    VICINITY. 

The  preparations  examined  representing  the  boulder-clay  of  Chicago 
and  vicinity  are  as  follows:  From  Chicago  lake  tunnel,  86  feet  down,  5 
slides;  North  Chicago  boulder-clay,  60  feet  down,  11;  North  Chicago  clay, 
64  feet  down,  2;  North  Chicago,  65  feet  down,  10;  corner  of  Washington 
and  Clark  streets,  eight  feet  down,  i ;  or  29  in  all.  These  are  so  similar  in 
their  general  characters  and  the  class  of  objects  which  they  present  that 
they  may  be  considered  together. 

The  inorganic  material  in  these  clays,  as  represented  by  the  above  prep- 
arations, consists  largely  of  quartz  sand,  in  which  few  well-rounded  grains 
appear,  most  being  sub-angular  and  many  quite  angular  and  unworn.  With 
these   is  a   notable  proportion    of    bottle  green  particles  of   hornblende, 

*It  should  be  explained  that  the  material  referred  10  in  the  succeeding  notes  is  that 
part  of  the  boulder-clay  which  is  romposed  of  pirticles  of  medium  size,  from  which  the 
very  fine  matter  has,  as  a  rule,  been  separated  by  decantation.  This  again  has  been  sized 
by  repeated  decantations  at  intervals  of  one,  two  or  three  minutes.  Mr.  Thomas  states 
that  the  greater  number  of  examples  of  a  given  form  are  frequently  thus  obtained  in 
material  of  a  certain  grade  of  fineness. 


6i 

with  a  few  of  mica  and  feldspar.  Nearly  one-half  of  the  entire  material  is, 
however,  composed  of  flatteneii  and  rounded  grains  of  fine  shale,  which 
have  a  dark  brown  color  and  granular  texture  by  transmitted  light.  One 
or  two  of  the  quarlz  grains  show  included  crystals,  and  many  hold  fluid  or 
gas  cavities.  The  bodies  of  organic  origin  most  commonly  met  with  are 
referable  to  Sporangites  {Protosalvinia)  Huronensis,D3i\\s,ox\,  of  the  Devonian 
shales.  These  are  extremely  abundant,  and  the  shale  particles  already 
described  are  doubtless  derived  from  the  disintegration  of  the  same  beds. 
They  are  in  some  instances  very  well  preserved,  but  are  also  present  in  all 
stages  of  decay,  and  in  many  cases  hold  a  (juantity  ^i  granular,  shaly,  or 
clayey  matter  in  their  interiors.  Besides  these  a  specimen  occurs  in  the 
material  from  the  lake  tunnel  of  entirely  different  character.  It  is  a  partly 
flattened  sphere  of  0.2  m.  m.  in  diameter,  with  radiating  and  concentric 
structure,  brownish  color,  and  very  small  central  cavity,  or  nucleus.  This 
is  similar  to  some  of  the  bodies  from  the  Devonian  rocks  described 
as  macrospores  by  Mr.  Clarke  in  his  paper  above  referred  to.  Two 
more  bodies  of  the  same  class  appear  in  other  preparations,  but  are  more 
nearly  transparent,  and  evidently  in  a  different  state  of  preservation.  To 
one  of  them  a  small  fragment  of  the  matrix  attaches  and  serves  to  show 
that  both  of  these  may  have  come  from  a  lime-stone  bed. 

Next  in  abundance  to  the  Sporangites  is  a  class  of  bodies  the  true  nature 
of  which  is  very  doubtful.  Of  these  at  least  twelve  large  fragments  were 
noted  in  the  preparations  under  discussion,  with  many  smaller  and  less 
characteristic  pieces.  They  may  be  described  as  spines  or  spicules,  gen- 
erally cylindrical,  but  sometimes  trough-shaped  or  triangular  in  cross-sec- 
tion, averaging  about  .05  m.  m.  in  diameter,  and  of  pale  yellowish  brown 
color.  Their  structure  is  very  finely  granular,  and  the  outer  surface  more 
or  less  roughened,  as  though  from  erosion.  TLey  are  in  some  cases  dis- 
tinctly tubular,  with  a  small  central  cavity;  others  have  a  thick  medullary 
portion,  which  is  poorly  defined,  but  differs  somewhat  In  texture  from  the 
exterior.  Some  of  the  fragments  terminate  in  acute  points,  others  have  a 
slightly  jwollen,  rounded  end,  and  one  was  observed  to  be  doubly  termin- 
ated and  nearly  spindle  shaped.  They  appear  to  be  calcareous,  but 
whether  this  is  their  original  condition,  or  the  result  of  mineralization,  is 
uncertain.  They  can  scarcely  be  cbitinous,  being  much  paler  in  color  than 
other  specimens  of  this  character  met  with  in  some  of  the  preparations.  So 
many  organisms  may  have  produced  spines  or  spicules  resembling  these 
bodies  that  it  is  not  yet  possible  to  assign  them  definitely.  They  do  not 
appear  to  be  sponge  spicules,  but  as  their  color  and  texture  is  not  unlike 
that  of  the  next  class  of  objects,  they  may  possibly  be  partly  mineralized 
chitinous  setae  of  Annelids,  derived  from  some  of  the  subjacent  rocks. 
Their  diversity  in  shape  is  such  that  they  must  either  represent  several  spe- 
cies or  belong  to  different  parts  of  some  organism  in  connection  with  which 
several  types  of  appendage  of  this  character  were  developed.     (Fig,  i.) 


6i 

Among  the  most  interesting  bodies  found  in  these  clays  are  certain 
comblike  objects  which  are  regarded  as  Annelid  jaws.  Of  these,  four,  all 
fragmentary,  have  been  observed.  'I'licy  were  at  first  supposed  to  be  teeth 
from  tlie  lingual  ribbon  of  some  mollusk,  but  on  more  careful  examination 
were  found  to  be  unlike  the  teeth  of  any  mollusk  of  which  figures  can  be 
found,  and,  moreover,  to  correspond  almost  exactly  in  form  witb.  some  of 
the  Annelid  jaws  dt  scribed  by  Mr.  G.  J.  Hinde  from  the  Silurian  and  Devo- 
nian rocks  of  Canada. f  One  of  the  specimens  shows  a  series  of  long  and 
curved  pro.^".  (Fig.  2.)  Three  others  apparently  belong  to  a  single  type, 
in  which  a  nearly  fiat  plate  is  armed  along  one  edge  with  a  series  of  small, 
close  denticles  arranged  somewhat  obliquely  to  the  line  of  attachment. 
(Fig.  3.)  Like  the  bodies  last  described  they  are  of  a  pale  straw  color,  dif- 
fering in  this  respect  from  Mr.  Hinde's  specimens,  which  are  said  to  be 
shining  and  black  ;  but  this  difference  may  arise  from  the  mode  of  pres- 
ervation. They  exhibit  no  reaction  with  polarized  light,  and  are  smooth 
antl  not  distinctly  granular.  The  ends  of  the  prongs  or  denticles  are  worn 
and  roughened  as  though  by  use. 


^ 


Fig.  I  (X130)  Fig.  a(xi3o)  Fig  .5  (X130) 

Organisms  from  the  Chicago  boulder-clays. 

Other  bodies  occurring  in  these  preparations  in  smaller  numbers  need 
not  be  referred  to  in  detail.  1  wo  broken  specimens  evidently  represent 
Ostracoda.  They  show  no  well  marked  sculpture,  but  a  minutely  ranular 
structure.  The  most  perfect  is  .31  m.  m.  in  length.  A  third  specimen, 
somewhat  larger,  and  also  broken,  is  either  a*  small  Sphaerium  or  a  very 
young  specimen  of  some  larger  shell.  All  three  have  adhering  to  them 
brownish  shaly  particles,  which  appear  to  indicate  their  o.igin,  though  it 
must  be  remarked  that  the  shell  substance  is  very  well  presv^rved  and  fresh- 
looking.  Still  another  specimen  is  a  broken  piece  of  the  edge  of  a  large 
calcareous  shell  or  carapace,  beautifully  marked,  and  possibly  that  of  an 
ostracod  of  another  species.  The  remaining  objects  observed  are  mere 
fragments,  quite  indeterminate  in  character.  Among  these  are  small  pieces 
of  a  delicate  ribbed  shell,  the  ribs  being  square  in  cross-section;  a  rather 
large  chitinous  fragment,  striated  externally,  but  without  any  orher  apparent 
structure,  and  one  or  more  pieces  of  straight  tubular  siliceous  spicules  prob- 
ably belonging  to  some  sponge. 

The  probable  sources  of  the  organic  bodies  in  these  clays  is  discussed 
subsequently  in  connection  with  those  from  other  places. 

f  Quarterly  Journal  of  the  Geological  Society,  1879,  p.  370. 


63 

BOULDER-C.LAVS    [-KOM    BLOOMINd  lON,   ILL.,    IO7    1  EET    DOWN. 

This  clay  "nimediately  underlies  an  interglacial  deposit  of  soil  and 
peaty  matter  with  remains  of  wood,  etc.*  Of  this  clay  five  preparations 
only  have  been  examined.  The  coarse  material  is  here  chiefly  quartz  sand, 
of  which  by  far  the  larger  proportion  is  sub-angular.  There  are  also  a  few 
grains  of  amethystine  (luart/,,  showing  sharp  conchoidal  fracture.  Several 
quartz  grains  show  inclusions,  one  of  very  small  hexagonal  red  crystals, 
probably  hematite.  Hornblende  urains  are  moderately  abundant,  but  shaly 
fragments,  such  as  those  whic'  e  up  a  large  proportion  of  the  material 

from  the  Chicago  clays,  are  ahki...  ;  altogetiier  wanting.  A  few  Macrospores 
exactly  like  those  previously  noticed  occur,  together  with  one  or  two  speci- 
mens of  the  pale  brownish  granular  spines,  or  setiB,  found  in  the  Chicago 
clays.  A  small,  flat,  curved,  finely -ribbed  body  in  one  of  the  slips  resem- 
bles part  of  the  edge  of  a  carapace.  While  therefore  not  altogether  want- 
ing in  this  clay,  organic  traces  appear  to  be  very  scantily  represented. 

BOULDER-CLAYS    FROM    MEEKER   COUNT/,    MINN. 

1'his  material  is  derived  from  a  well  shaft  sunk  in  Meeker  County,  at  a 
depth  of  about  twenty-two  feet,  and  was  transmitted  to  Mr.  Thomas  by 
Prof.  N.  H.  Winchell,  State  geologist  of  Minnesota.  Mr.  Thomas  has 
made  a  large  series  of  preparations  from  it,  a  number  of  which  I  have  had 
the  opportunity  of  inspecting. 

As  the  Foraminifera  contained  in  these  preparations  are  being  named 
and  catalogued  by  Messrs.  A,  Woodward  and  B.  W.  Thomas,  the  remarks 
here  given  are  confined  principally  to  the  general  character  and  contents  of 
the  clay,  with  the  object  of  comparing  it  with  those  from  other  localities. 

The  coarser  material  from  this  clay,  as  it  appears  in  the  p.eparations,  is 
chiefly  quartz  sand,  which  is  generally  sub-angular,  though  with  some  well- 
rounded  grains.  Hornblende  and  mica  appear  in  about  the  usual  propor- 
tions, and  two  quartz  grains  with  very  beautiful  inclusions  were  noticed,  one 
being  probably  either  hornblende  or  -utile,  the  other  possibly  apatite.  A 
large  proportion  of  the  material,  however,  consists  of  rounded  grains  of 
shale,  of  gray  or  greenish-gray  color  by  transmitted  light,  and  not  nearly  so 
dark  as  the  shale  mixed  with  the  Chicago  clays.  In  specimens  boiled  in 
nitric  ac'..,  the  shaly  fragments  have  become  reddish  from  the  oxidation  of 
their  iron. 

Of  organic  bodies  present  in  these  specimens  ot  Minnesota  clay,  the 
Foraminifera  are  most  prominent  and  important.  They  are  evidently 
derived  from  the  Cretaceous  strata,  and  resemble  those  found  in  the  western 
d  -elopment  of  these  rocks,  both  specifically  and  in  mode  of  preservation. 
RotalidcB  and  Textularidce  are  most  abundant,  though  specimens  of  Glo- 
big     na  and  other  genera  also  occur.     Next  in  abundance  to  the  Foramin- 

*Thia  stratum  of  soil  is  about  G  feet  thick,  and  underUes  101  feet  of  boulder-clay.  1  do  not  know 
the  thicicness  of  the  clay  deposit  below  the  iuter-glacial  soil,  but  both  i.iie  upper  and  lower  clay  deposits 
carry  an  abundance  of  glacial-marked  boulders. — B.  W.  T. 


64 

ifera  are  remains  oi  Radiolaria.  Some  difificulty  was  experienced  in  decid- 
ing the  true  nature  of  fragments  of  these  bodies  at  first  met  with,  but  the 
subsequent  discovery  of  numerous  and  often  well-preserved  specimens,  and 
the  observation  by  Mr.  Thomas  that  they  resist  boiling  in  nitric  acid,  now 
leave  no  doubt  as  to  their  character.  Several  genera  and  quite  a  number 
of  species  are  represented,  and  it  will  eventually  be  possible  to  determine 
many  of  these  forms  specifically.  Most  appear  to  belong  to  the  Polysphaer- 
idae  and  Cystidse  of  Haeckel's  classification.  The  constant  occurrence  of 
these  bodies  with  the  Cretaceous  Foraminifera  in  the  Minnesota  preparations 
and  in  those  ^'om  other  places,  with  their  absence  from  materials  not 
equally  characterized  by  the  Foraminifera,  leaves  little  room  to  doubt  the 
common  origin  of  both.  Among  miscellaneous  objects  from  the  Minnesota 
clay  may  be  mentioned  a  few  fragments  apparently  identical  with  the  min- 
utely granular  spines  or  seise  described  as  occurring  in  the  Chicago  clays; 
also  two  broken  portions  of  stout  siliceous  spicules,  about  .026  m.  m.  in 
diameter,  one  smooth,  the  other  tuberculated ;  both  tubular,  and  probably 
belonging  to  some  sponge.  Lastly,  a  single  specimen  of  a  very  curious 
body,  of  straggling  and  irregular  form,  composed  of  numerous  expansions 
differing  in  shape  and  size  and  pretty  uniformly  pitted  and  connected  by 
narrow,  smooth  necks.  As  this  is  in  one  of  the  preparations  which  has  been 
treated  with  acid,  it  must  be  siliceous.  I  can  only  suggest  that  it  may  be 
the  siliceous  cast  of  some  foraminifer  like  Aschemonella  catenata  of  Norman 
the  arenaceous  test  of  which  has  been  composed  of  calcareous  particles 
which  have  left  pitted  impressions  on  the  cast.  Against  this  is  the  fact  of 
its  small  size,  it  being  about  .2  m.  m.  only  in  greatest  diameter. 

BOULDER-CLAY   FROM   CRETE,   SALINE   CO.,    NEB. 

This  material,  Mr.  Thomas  informs  me,  was  obtained  from  a  single  small 
excavation.  It  was  forwarded  to  Mr.  Thomas  by  Prof.  G.  D.  Swezey,  and 
is  described  by  him  in  a  letter  to  Mr.  Thomas  as  a  blue  clay  underlying  the 
loess.  The  inorganic  matter  in  the  preparations  made  from  it  consists 
largely  of  fine  angular  and  sub  angular  quartz  grains,  with  a  small  proportion 
of  green  hornblende  and  much  shale  or  earthy  limestone  in  little  particles  | 
which  differ  in  color  and  texture.  It  is  extremely  rich  in  organic  forms, 
chiefly  Cretaceous  Foraminifera,  so  much  so  that  it  seems  probable  that  it  is 
largely  composed  of  the  debris  of  the  Niobrara  division  of  that  formation, 
and  that  a  complete  study  of  its  contents  would  practically  include  that  of 
all  the  forms  occurring  in  the  chalky  limestone  of  that  scage.  The  present 
notice  of  it  must  therefore  be  considered  as  of  the  most  general  and  prelim- 
inary character  only.  Of  this  material  a  suite  of  thirty-one  preparations 
has  be^n  examined,  and  in  an  enumeration  of  about  one  hundred  of  the 
best  preserved  forms,  nearly  fifty  per  cent  belong  to  the  Texiuluridee,  the 
remainder  being  made  up  in  nearly  equal  proportions  of  Globigerinida, 
RotalidcBy  miscellaneous  Foraminifera  of  other  families,  and  RadiolarianSj 


s 


65 

resembling,  and  in  some  cases  identical  with,  the  Minnesota  species.  Frag- 
ments of  calcareous  prisms  from  the  shell  of  Inoceramus  and  in  the  finer 
matter  specimens  of  Coccoliths  and  Rhahdoliths  also  occur ;  all  resembling 
in  every  respect  Similar  bodies  found  in  the  Niobrara  rocks  of  Nebraska  and 
Manitoba.* 

Many  of  the  Foraminifera  are  completely  filled  with  calcite,  while  oth- 
ers are  still  partially  hollow,  and  yet  others  are  filled  partly  with  calcite  and 
partly  with  black  carbonaceous  or  bituminous  matter.  Of  objects  of  an  unus- 
ual character  two  may  be  specially  referred  to.  A  rod-like  body  about  .2  m. 
m.  in  length,  narrowed  near  the  middle,  though  broken  at  one  end,  and  marked 
by  numerous  pits  in  linear  series.  This  may  be  a  small  spine  from  some 
Echinoderm.  Also  a  hollow  conical  tooth  or  spine,  evidently  that  of  a 
fish,  also  broken,  but  still  .25  m.  m.  in  length. 

BOULDER-CLAV    FROM   A   WELL   AT    ROSENFELD,    MANITOBA. 

This  material,  sent  to  me  under  the  name  of  '-  Hard-Pan,"  was  obtained 
at  a  depth  of  135  feet,  in  a  well  bored  by  the  Canadian  Pacific  Railroad 
Company  at  Rosenfeld,  Manitoba.  It  formed,  mixed  with  gravel  and 
boulders,  a  layer  of  eighteen  feet  in  thickness,  below  the  post-glacial  allu- 
vial deposits  of  the  Red  River  Valley  and  resting  on  a  Silurian  shale.  As 
the  well  was  bored  with  an  ordinary  percussion  drill,  it  is  possible  that  some 
matter  from  the  alluvial  deposits  above  referred  to  may  have  been  mixed 
with  the  specimen  of  "hard-pan,"  but  so  far  as  examined  these  alluvial 
deposits  do  not  hold  any  organic  forms.  Numerous  small  particles  of  steel 
from  the  edge  of  the  drill  occur  in  the  six  preparations  representing  this 
clay. 

The  inorganic  constituents  are  coarse  in  texture  ;  quartz  grains,  of  which 
nearly  one-half  are  perfectly  rounded,  as  usual  predominating.  Bottle- 
green  hornblende  is  moderately  abundant  as  are  also  fragments  of  feldspar 
and  limestone,  but  shaly  materials  are  almost  altogether  wanting.  Bodies  of 
organic  origin  are  rather  scarce,  Foraminifera,  however,  being  most  com- 
mon, and  a  Textularia  of  the  type  of  T.  globulosa  is  characteristic.  A  few 
Rotalidae  are  also  present,  with  broken  chambers  of  other  Foraminifera. 
The  examination  of  a  greater  quantity  of  the  material  would  doubtless  lead 
to  the  discovery  of  all  the  ordinary  Cretaceous  types. 

BOULDER  CLAY    FROM    THE   SOUTH    SASKATCHEWAN    RIVER  TEN   MILES    EAST   OF 

THE  MOUTH  OF   THE  SWIFT  CURRENT. 

This  and  the  two  following  localities  in  the  Canadian  northwest  terri- 
tory are  represented  by  specimens  collected  by  Mr.  R.  G.  McConnell.  The 
three  localities  lie  between  the  io6th  and  io8th  meridians,  and  represent  a 
portion  of  the  great  drift-covered  area  of  the  northern  plains.  The  material 
from  this  place  is,  as  usual,  largely  siliceous,  but  there  is  a  larger  proportion 

'''See  a  paper  by  the  writer  in  the  Canadian  Naturalist,  1874. 


66 

than  common  of  coarse,  thoroughly-rounded  quartz  grains.  Hornblende 
and  other  crystalline  minerals  from  the  Laurentian  or  Huronian  are  also 
present,  and  there  is  a  notable  (juantity  of  amethystine  quartz  in  angular 
fragments.  Comminuted  gray  shale,  very  finely  ground,  is  moderately 
abundant.  Bodies  of  organic  origin  are  not  frequent.  In  pretty  carefully 
examining  a  series  of  >ix  preparations,  about  ten  only  were  met  with.  These 
are  Textularice  and  rotaline  Foraminifera,  with  one  very  small  Globigerina 
and  a  couple  of  Radiolarians ;  one  very  perfect,  oval  and  .09  m.  m.  longest 
diameter.  {^Haliomma  ? )  A  fragment  was  also  found  of  bony  substance, 
showing  haversian  canals  and  probably  portion  of  a  ganoid  scale.  There  is 
also  in  these  preparations  a  number  of  rounded  and  flattened  grains,  nearly 
transparent,  though  in  some  cases  with  a  more  opaque  central  spot,  and 
surface  minutely  and  regularly  roughened.  These  were  eventually  deter- 
mined by  comparison  to  be  fragments  of  some  pearly  shell,  probably  that 
of  Unio,  a  form  quite  abundantly  represented  in  the  Cretaceous  and  Laramie 
rocks  of  the  region.  The  appearance  of  an  opaque  nucleus  in  some  examples 
appears  to  result  from  tiie  non-penetration  of  the  mounting  medium  to  the 
centre  of  the  larger  grains. 

BOULDER-CLAV  FROM   TEN  MILES  NORTH  OF    THE  SOUTH    SASKATCHEWAN,  EAST 
OF    MISSOURI    COTEAU,    TOWNSHIP    21,    RANGE    10,  WEST  OF    3D  PRINCIPAL 

MERIDIAN. 

The  material  in  six  preparations  from  this  clay  differs  from  the  last 
described  only  in  the  much  greater  quantity  of  comminuted  shaly  matter  of 
a  reddish-brown  tint.  Bodies  of  organic  origin  are  here  again  scarce.  No 
Foraminifera  were  found.  Two  or  three  broken  pieces  of  minute  rod-like 
pitted  objects,  very  doubtfully  referred  to  small  spines  of  some  Echinoderm, 
and  evidently  identical  in  character  with  that  previously  described  from 
Saline  County,  Neb.,  were  detected.  Those  occurring  here  are  about  .015 
m.  m.  in  diameter.  Another  somewhat  similar  object  is  rather  stouter  and 
with  a  roughened  surface  without  regular  markings.  A  small  broken  piece 
of  some  chitinous  test  was  also  observed,  but  on  the  whole  this  material  is 
very  barren. 

BOULDER-CLAV  FROM   THfc    SOUTH  SASKATCHEWAN,   FIFTEEN    MILES  ABOVE   THE 

ELBOW. 

In  the  preparations  from  this  clay — eighteen  in  number — the  sandy 
material  is  n  uch  finer  than  in  the  two  last.  It  is  nearly  half  composed  of 
shaly  fragments  of  brown  color,  the  quartz  sand  being  also  rather  more 
angular  than  usual.  It  is  richer  in  organic  forms  than  either  of  the  other 
specimens  from  the  neighbo  hood  of  the  South  Saskatchewan.  About  half 
a  dozen  specimens  of  Foraminifera  were  recognized  in  the  preparations, 
one  being  probably  a  small  Discorbina,  others  Textularice  and  broken 
chambers  of  Globigerince.     These  are  not  so  well  preserved  as  in  some  of 


67 

the  other  clays,  and  in  some  cases  the  shell  itself  appears  to  have  been 
removed,  leaving  only  a  rough  cast  in  calcite.  Radioiarians  are  here  (so 
far  as  the  examination  of  a  small  <|uantity  of  material  can  be  accepted  as 
conclusive)  even  more  abundant  than  Foraminifera,  spherical,  oval  and 
turbinate  forms  all  being  represented,  and  in  some  cases  in  such  connection 
with  fragments  of  the  abundant  shaly  material  as  to  leave  no  doubt  as  to 
their  common  origin  with  it.  Small,  partly  rounded  prisms  from  the  shell 
o{  InocetatHus  are  also  present,  together  with  a  few  pieces  of  straight  hollow 
siliceous  sjjiculse,  one  specimen  of  a  minutely  granular  spine  or  seta,  with  a 
distinct  medullary  portion  like  some  previously  noticed,  and  .026  m.  m.  in 
diameter,  and  one  of  a  portion  of  a  body  like  that  previously  referred  with 
doubt  to  an  Echinoderm  spine. 

CONCLUSIONS. 

In  inquiring  as  to  the  derivation  of  the  various  organic  bodies  in  the  clays, 
it  is  necessary  to  consider  the  situation  of  each  locality  with  reference  to 
known  areas  of  the  older  rocks,  from  the  disintegration  of  which  they  may  have 
come.  The  Sporangites  so  abundant  in  the  Chicago  clays  have  been  defin- 
itely traced  to  the  shales  of  the  Devonian  age,  and  have  doubtless  been 
brought  to  their  present  position  from  outcrops  to  the  northward  in  the 
Michigan  peninsula.  It  has  already  been  stated  that  the  bodies  supposed  to 
be  Annelid  jaws  may  probably  have  been  derived  from  the  same  beds,  or 
from  others  of  the  Devonian  or  Silurian  rocks  of  this  part  of  the  country. 
With  regard  to  the  remaining  bodies  no  definite  statement  can  at  present 
be  ventured,  though  there  is  every  reason  to  believe  that  they  might  very 
well  have  come  from  the  same  rocks. 

In  the  clays  from  Bloomington,  in  the  center  of  the  State  of  Illinois, 
Sporangites  are  again  the  most  characteristic  bodies,  though  much  less 
numerous  in  correspondence  with  the  greater  distance  from  the  shale  out- 
crops.' A  {^\;  other  objects  associated  with  these  are  not  dissimilar  to  those 
in  the  Chicago  clays. 

Meeker  County,  from  which  the  specimens  of  Minnesota  boulder-clay 
were  derived,  is  in  the  southern  and  central  portion  of  the  State,  and  is 
underlaid,  according  to  Prof.  N.  H.  Winchell  by  rocks  of  the  Archaean 
period,  overlain  probably,  at  least  in  some  places,  by  shales  of  the 
Cretaceous.  As  might  be  anticipated  from  the  absence  of  Devonian 
rocks,  both  in  this  locality  and  the  whole  region  to  the  north  and  northeast, 
Sporangites  have  not  been  observed  in  this  clay.  While  the  greater  part  at 
least  of  the  organisms  are  evidently  referable  to  the  Cretaceous  rocks,  the 
locality  lies  to  the  northeast  of  tiie  generally  recogni.'ed  edge  of  that  forma- 
tion. Prof.  Winchell  has,  however,  proved  the  existence  of  a  number  of 
outliers  of  Cretaceous  beyond  the  main  area  occupied  by  these  rocks,  and  it 
is  probably  from  one  of  these,  possibly  !iot  remote  from  the  actual  position 
of  the  clay,  that  the  Foraminiferce  and  Radiolarice  have  come. 


68 

The  clay  from  Crete,  Saline  Co.,  Neb.,  is,  as  already  observed,  so  rich 
in  Cretaceous  forms  as  to  lead  to  the  belief  that  it  is  largely  composed  of 
the  debris  of  the  chalky  limestone  of  the  Niobrara  stage,  and  may  rest 
upon  or  lie  very  near  to  the  outcrop  of  these  beds.  I  am  not  in  a  position 
to  state  whether  the  geology  of  the  district  bears  out  this  conclusion.  The 
map  shows  at  least  that  Cretaceous  rocks  underlie  this  part  of  the  State. 

The  material  from  Rosenfeld,Mc:nitoba,  shows  a  smaller  number  of  forms, 
but  these  are  equally  characteristic  of  the  Niobrara  stage,  the  outcrop  of 
which,  though  concealed  by  alluvial  and  other  deposits,  can  not  be  many 
miles  west  of  the  position  of  the  well,  and  also  runs  northward  along  the 
base  of  the  Pembina  escarpment,  having  been  recognized  at  a  point  about  fifty 
miles  northwest  of  Rosenfeld  on  the  Boyne  River.  ("  Geology  and  Resourc- 
es of  the  49i;h  Pa"  "llel,"  p.  78).  As  there  is  little  probability  of  the  exist- 
ence of  any  Cret.  -eous  rocks  directly  north  or  to  the  northeastward  of  this 
place,  the  occurrence  of  Cretaceous  Foraminifera  would  tend  to  show  that 
material  derived  from  the  northwest  had  been  incorporated  with  the  boulder- 
clay  of  this  district. 

The  three  localities  near  the  South  Saskatchewan  may  be  treated  of 
together,  in  so  far  as  the  origin  of  their  organic  constituents  is  concerned. 
The  general  movement  of  the  material  composing  the  glacial  deposits  of  the 
northern  plains  in  a  southwesterly  direction  has  already  been  demonstrated 
(see  '•  Quarterly  Journal  of  the  Geological  Society,  1875,"  P-  ^^°5  >  "  Report 
of  Progress  of  the  Geological  Survey  of  Canada,  1882-84,"  p.  139),  and  it 
would  appear  tl  it  the  Cretaceous  Foraminifera  must  also  have  been  carried 
from  the  vi  inity  of  the  eastern  Cretaceous  outcrops  at  a  great  distance.  It 
is  true  that  t  '  clays  here  rest  on  Cretaceous  beds,  but  these  are  not  as  a  rule 
calcareous,  or  nch  as  to  yield  Foraminifera  in  the  state  of  preservation  of 
those  found  in  these  clays.  The  Niobrara  limestones  are  not  only  unknown 
in  the  entire  district  from  which  the  clays  come,  but  their  place  appears  to 
be  taken  in  this  region  by  the  Belly  river  beds,  which  are  arenaceous  and 
argillaceous.  Other  organic  fragments  present  in  these  clays  may  well  have 
been  derived  from  the  Cretaceous  or  Laramie  beds  of  the  immediate  neigh- 
borhood. 

In  reviewing  the  general  bearings  of  the  microscopical  examination  of 
these  boulder-clays,  representing  as  they  do  a  few  points  only,  scattered  over 
a  wide  area  in  the  central  portion  of  the  continent,  it  would  be  unwise  to 
endeavor  to  draw  any  very  definite  or  too  general  conclusions.  The  field 
appears  to  be  a  promising  one  for  future  inquiry,  and  the  present  paper  can 
be  regarded  only  as  in  the  strictest  sense,  preliminary.  It  would  appear, 
however,  that  of  all  the  organic  bodies  met  with  none  can  be  assigned  with 
certainty  to  the  glacial  period  or  era  of  deposition  of  the  boulder  clay  itself. 
The  origin  of  most  can  be  traced  unequivocally  to  the  older  rocks,  from 
which  they  have  been  derived,  and  incorporated  with  the  boulder-clays. 
Of  all  the  bodies  enumerated  the  only  ones  which,  on  account  of  their  pres- 


69 

lence  in  clays,  holding  otherwise  different  sets  of  forms,  may  possibly  be  of 
•contemporaneous  origin  with  them,  are  siliceous  sponge  (?)  spicules  and  the 
peculiar  spines  or  setae  several  times  referred  to  in  the  foregoing.  To  these 
may  be  possibly  added  the  Ostracoda  from  the  Chicago  clay.  While  it  is 
therefore  probable  that  the  examination  of  these  organic  fragments  will 
serve  to  throw  additional  light  on  the  direction  of  transport  of  material 
during  the  Glacial  period — a  pcint  of  particular  value  over  the  wide  area  of 
the  plains,  where  the  soft  character  of  the  rock  precludes  the  test  of  direction 
of  striation — it  has  so  far  failed  to  afford  any  certain  information  as  to  the 
actual  conditions  prevailing  during  that  period.  The  negative  evidence, 
reintbrced  by  the  fact  that  derived  bodies  have  been  perfectly  preserved,  so 
far  as  it  goes,  leads  to  a  belief  in  the  great  scarcity  of  contemporary  life. 
The  occurrence  of  inter-glacial  peats  and  the  inclusion  of  wood  and  other 
vegetable  matters  in  the  boulder-clays  of  a  number  of  widely  separated  local- 
itiesin  the  West  (see  *'  Vegetable  remains  in  Drift  Deposits  of  the  Northwest," 
by  Prof.  N.  H.  Winchell,  Proc.  A.  A.  S.,  1875  ;  "Report  of  Progress  of 
the  Geological  Survey  of  Canada,  1882-84,'"  P-  ^44)  prove,  however,  that 
life  was  not  constantly  absent,  and  it  may  therefoie  reasonably  be  anticipated 
that  further  search  will  eventually  leatl  to  the  definition  in  the  clays  of  at 
least  such  contemporary  organisms  as  may  have  been  derived  from  these 
inter-glacial  deposits,  and  possibly  of  others  strictly  contemporaneous  with 
the  boulder-clays  themselves.  The  well-rounded  character  of  a  considerable 
proportion  of  the  sand  in  some  of  the  specimens  points  to  prolonged  water 
action,  but  there  is  no  means  of  deciding  to  what  extent  in  each  case  pre- 
viously rounded  sand  grains  have  been  included  in  the  clays.  The  compar- 
atively unworn  appearance  of  the  majority  of  the  Foraminifera  and  other 
delicate  objects,  on  the  contrary,  indicates  rather  tranquil  conditions  of 
deposit,  and  negatives  the  occurrence  in  the  case  of  these  materials  of  any 
extensive  differential  motion  in  the  substance  of  the  clay  itself,  which  would 
infallibly  have  destroyed  these  very  fragile  organisms.  Mr.  Hugh  Miller, 
in  a  carefully  worked  out  paper  on  "  Boulder  Glaciation  "  ("  Royal  Physical 
Society,  Edinburgh,"  vol.  viii,  p.  157),  describes  a  fluxion  structure  in  the 
Scottish  till  or  boulder-clay,  and  notes  instances  of  sand  grains  so  shaped 
and  striated  as  to  represent  microscopic  glaciated  boulders  which  he  con- 
ceives to  have  been  "  slidden  along  and  glaciated  in  these  places  in  the 
clay."  No  confirmation  of  this  observation  is  afforded  by  these  clays. 
Though  many  grr  ns  of  an  elongated  shape  show  what  might  at  first  be 
taken  for  such  striation,  it  is  a})parent  in  almost  every  case  on  close  exam- 
ination that  the  lines  are  really  structural  and  that  the  shape  of  the  grains  is 
here,  as  in  ordinary  sands,  governed  to  a  great  extent  by  the  pre  existing 
cleavage  or  jointage  planes  of  the  material  of  which  they  are  composed. 

The  microscopical  examination  of  these  boulder-clays  bears  out  the  con- 
clusion arrived  at  from  their  macroscopic  characters  that,  while  largely  com- 
posed of  far-traveled  material,  they  invariably  contain  a  considerable  pro- 
portion of  material  of  local,  or  proximately  local,  origin. 


